Merge 281795 "base: Add soft memory limit to DiscardableMemoryMa..."

base/memory/discardable_memory_emulated.cc

Index: base/memory/discardable_memory_emulated.cc
===================================================================
--- base/memory/discardable_memory_emulated.cc	(revision 283285)
+++ base/memory/discardable_memory_emulated.cc	(working copy)
@@ -19,7 +19,9 @@
 struct SharedState {
   SharedState()
       : manager(kEmulatedMemoryLimit,
-                kEmulatedBytesToKeepUnderModeratePressure) {}
+                kEmulatedMemoryLimit,
+                kEmulatedBytesToKeepUnderModeratePressure,
+                TimeDelta::Max()) {}
 
   internal::DiscardableMemoryManager manager;
 };
@@ -52,6 +54,11 @@
 }
 
 // static
+bool DiscardableMemoryEmulated::ReduceMemoryUsage() {
+  return g_shared_state.Pointer()->manager.ReduceMemoryUsage();
+}
+
+// static
 void DiscardableMemoryEmulated::PurgeForTesting() {
   g_shared_state.Pointer()->manager.PurgeAll();
 }